| Fabria inornata | Larva - case | Merritt p. 381 fig. 18.234 |
| Fabria inornata | Larva - pronotum dorsal view | Merritt p. 381 fig. 18.236 |
| Fallceon quilleri (Baetis endymion) | Imago - hind wing | Needham p. 685 d |
| Fallceon quilleri (Baetis erebus) | Imago - hind wing | Needham p. 685 b |
| Fallceon quilleri (Baetis erebus) | Imago - male genitalia | Needham p. 688 b |
| Fallceon quilleri (Baetis quilleri) | Imago - hind wing | Needham p. 685 h |
| Farrodes | Larva - labrum | Merritt p. 142 fig. 11.91 |
| Farrodes | Larva - tarsal claw | Merritt p. 142 fig. 11.92 |
| Farrodes texanus | Imago - genitalia ventral (male) | Merritt p. 157 fig. 11.180 |
| Farrodes texanus | Larva - head dorsal | Merritt p. 142 fig. 11.90 |
| Farula | Imago - wings | Merritt p. 335 fig. 17.128 |
| Farula | Larva - ab2 lateral | Merritt p. 383 fig. 18.266 |
| Farula | Larva - case | McCafferty p. 262 fig. 14.64 |
| Farula jewetti | Larva - pro & mesathorax dorsal | Merritt p. 386 fig. 18.284 |
| Fattigia | Imago - head & throax | McCafferty p. 265 fig. 14.76 |
| Fattigia | Larva - abdomen posterior dorsal | McCafferty p. 265 fig. 14.75 |
| Fattigia | Pupa - head frontal | Merritt p. 331 fig. 17.99 |
| Fattigia | Pupa - abdomen dorsal | Merritt p. 331 fig. 17.97 |
| Fattigia | Larva - head, thorax, ab1 lateral | Merritt p. 325 fig. 17.74 |
| Fattigia | Pupa - anal proces lateral | Merritt p. 331 fig. 17.98 |
| Fattigia pele | Larva - head lateral view | Merritt p. 383 fig. 18.263 |
| Ferrissia | Ametabolous - ventral view | Bouchard p. 29 fig. 2.82 |
| Forcipomyiinae | Larva - larva | McCafferty p. 308 fig. 16.41 |
| Frenesia | Imago - lateral view | LaFontaine p. 267 - b |
| Frenesia | Larva - case | LaFontaine p. 267 - a |
| Frenesia | Adult - lateral | Pobst - p. 84-a |
| Frenesia | larva - cased lateral | Pobst - p. 84-b |
| Frenesia missa | Imago - lateral view | LaFontaine p. 154 |
| Frenesia missa | Larva - pronotum dorsal view | Merritt p. 373 fig. 18.185 |
| Frisonia pictipes | Larva - left lacinia ventral | Merritt p. 238 fig. 14.90 |
| Frisonia pictipes | Larva - mesosternum ventral | Merritt p. 238 fig. 14.88 |
| Fucellia separata | Imago - adult | McCafferty p. 358 fig. 17.22 |